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kit
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ibit_shift_combo.c (620B)

      1 /* Mixed shift+mask idiom: extract a byte field via a logical right shift
      2  * followed by an AND mask, and rebuild via a left shift + OR. Exercises the
      3  * shift forms feeding directly into and/orr (the common bitfield pattern) so
      4  * the operand chaining round-trips. volatile defeats folding.
      5  *   x = 0x2A3B;  (x >> 8) & 0xFF = 0x2A (42)
      6  *   y = 0x10;    (y << 2) | 0x02 = 0x42 -> & 0x3F = 0x02 (2)
      7  *   42 + 2 - 2 = 42. */
      8 int test_main(void) {
      9   volatile unsigned int x = 0x2A3B;
     10   volatile unsigned int y = 0x10;
     11   int hi = (int)((x >> 8) & 0xFF);
     12   int lo = (int)(((y << 2) | 0x02) & 0x3F);
     13   return hi + lo - 2;
     14 }